Fact Sheet OPTIMUS Plant Growth Regulator An Emulsifiable Concentrate (EC) containing 175 g/litre trinexapac-ethyl OPTIMUS is a plant growth regulator that reduces the risk of lodging in Wheat, Barley and Oats and promotes seed yield increases in Ryegrass seed crops. OPTIMUS is absorbed rapidly through the leaves and stems of grass plants and moves quickly to the growing points. Trinexapac-ethyl is converted to trinexapac in the plant tissue and slows growth by inhibiting gibberellin synthesis. This reduces cell elongation which shortens internode length and this reduces plant height. In ryegrass, shortened straw length delays lodging which improves pollination and results in increased seed set. OPTIMUS is a highly effective new generation formulation of trinexapac-ethyl containing an improved adjuvant system of longer chain fatty acids. These lower the surface tension to give maximum spreading of spray droplets on green tissue and increase lipophilic (oil or wax compatibility) properties. Water droplets have high surface tension and do not spread over the waxy (hydrophobic) leaf surface Since the wax layer on the surface is also lipophilic, droplets of OPTIMUS spray mix spread much more effectively than standard formulations and bonding with the waxy surface results in a more efficient uptake of trinexapac-ethyl into the leaf...
The OPTIMUS Advantage Leaf surface wax layer repels water (hydrophobic) Water droplets have high surface tension Water droplets do not spread OPTIMUS spray droplets have low surface tension Low surface tension gives maximum spreading OPTIMUS spray mix is lipophilic (compatible with oils & waxes) The waxy outer layer of the leaf is also lipophilic This optimises spread, uptake and efficacy OPTIMUS : Spray Droplet Characteristics Droplets of OPTIMUS spray mix OPTIMUS: Maximum surface area contact with the leaf surface = increased and more efficient uptake of trinexapac-ethyl. The unique lipophilic surfactant in OPTIMUS enables the spray mix droplets to spread more evenly and bond with waxy plant surfaces. Increased contact area plus lipophilic action results in maximum uptake of trinexapac-ethyl into the plant.
Droplets of Standard spray mix STANDARD: Lower surface area contact with the leaf surface plus reduced penetration of the waxy layer = less trinexapacethyl uptake. Standard formulations of trinexapac-ethyl do not spread as effectively and have low affinity with the waxy leaf surface layer. This results in inconsistent uptake and the uptake can vary from plant to plant. OPTIMUS: Measurement of uptake C14 study 14 C Content (+/-1SE) in leaf (% of applied dose) 14 C Content in wheat & barley leaves treated with 14 C- trinexapac formulations Hours after treatment Less OPTIMUS active ingredient is left on the leaf surface than with standard formulations. More OPTIMUS active ingredient enters the leaf More efficient conversion of trinexapac-ethyl to trinexapac inside the leaf More effective activity Optimus Wheat Optimus Barley Known brand Trinexapac Wheat Known brand Trinexapac Barley
14 C Study : Wheat leaf autoradiograms After 1 hour After 24 hours OPTIMUS Leading Brand OPTIMUS Leading Brand DIRECTIONS FOR USE: Ryegrass Use Rate Critical Comments Increasing seed set 575ml 1.15L in 200 to 400 litres of water/ha Apply at the GS31-32 growth stage. When the 2 nd node is visible on the main tiller and the majority of the other tillers have the 1 st node detectable above ground level. The higher rate is recommended on high fertility paddocks where there is no moisture stress e.g. under irrigation. OPTIMUS should be applied to actively growing ryegrass NOT suffering from disease, drought stress or insect damage. Timing of application is critical to get the best results. Use a sharp knife to split a random selection of tillers from across the paddock. The average growth stage should be determined from this assessment and Optimus applied as near as possible to GS32 to achieve the best result. Under conditions where it may not be possible to apply at the exact stage, early application is more effective than late application. Ryegrass at stage GS31-32 on 50% of tillers
Standard use rates for OPTIMUS range from 575 ml/ha to 1.15 litres/ha, but trials by FAR and others over many seasons and local grower experience have shown that a wider range of rates can be used. To get the best results always consult local experts for advice well before application. Rates can be varied for different varieties (annual, perennial and turf varieties), under different growth conditions such as cool or warm, dry, normal, wet or irrigated crops, or to crops under stress. Cereals Crop Use Rate Critical Comments Wheat, Barley, Oats Reduction of lodging 575ml/Ha in 200litres water Apply at the beginning of stem elongation as the 1 st node becomes visible (GS31). OPTIMUS should be applied to actively growing cereals NOT suffering from disease, insect damage, drought stress or nutrient deficiency. The addition of a surfactant is NOT necessary... OATS : The recommended rate of OPTIMUS may cause severe stunting in oats, however final yield should be unaffected Tank mixing with chlormequat (CCC) is recommended for use on cereals. A typical use rate is 1.5L/Ha of 750 g/l chlormequat formulation. Consult a local expert for information on recommended chlormequat use rates. WITHHOLDING PERIOD Ryegrass 42 days It is an offence for users of this product to cause residues exceeding the relevant MRL in the New Zealand (Maximum Residue Limits of Agricultural Compounds) Food Standards. COMPATIBILITY & MIXING: OPTIMUS is compatible with other commonly used fungicides, insecticides and plant growth regulators. Consult a local expert before tank mixing with herbicides. OPTIMUS mixes readily with water. Under agitation, add the required amount of OPTIMUS to the partly filled spray tank while adding the remainder of the water. IMPORTANT: This is not the registered label. Always read the label before using this product and follow label instructions. For specialist advice in an EMERGENCY call 0800 734 607 (all hours). Registered pursuant to the ACVM Act 1997, No. P8562. See www.foodsafety.govt.nz for registration conditions Approved pursuant to the HSNO Act 1996, Approval No. HSR100710. See www.epa.govt.nz for approval controls. HSNO classifications: 6.3A, 6.4A, 6.5B, 9.1D, 9.2A Adama and Optimus are trademarks of an Adama Group Company. Release date: 31.07.12